Abstract:

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M-TiO2 (M = Ag, Cu) nanocomposite layers were grown by pulsed direct liquid injection chemical vapor deposition (DLICVD) on various substrates to produce bactericidal surfaces with long term activity. Monodisperse Ag nanoparticles (NPs) with an average size of 5-10 nm are embedded in an anatase matrix. A bactericidal behavior determined by the JIS Z 2801 standard test was found for Ag-TiO2 films for Ag ≤ 1 at. % and above. Higher Ag content is not necessary since efficiency is already at its maximum (relative activity 100%). By contrast, using Cu as antibacterial agent, a larger size distribution of metal particles was found (20 to 400 nm). Cu-TiO2 films exhibit a bactericidal behavior if their thickness is higher than 100 nm and Cu content ≥ 3.5 at. %. These coatings are still antibacterial after 5 months of aging and their efficiency has decreased by only 35%.

Abstract: After solid-solution and aging treatment, the copper-bearing ferritic stainless steel has
been investigated by TEM fitted with X-ray EDS and XPS methods. The TEM and EDS shown that
the rod-like precipitation phase was є-Cu, and distributed dispersively throughout in the matrix. The
most important result from XPS analysis confirmed that except the topmost of passive film, copper
appeared as element state and its concentration kept constant in the inner surface of the material. It
was found that the material shown an excellent antibacterial property to staphylococcus and
coliform bacteria, after passive film elimination,

Abstract: The antibacterial effects of titanium oxide/calcium phosphate and calcium phos-phate/copper phosphate composite coatings have been investigated. Implant-like rough blasted tita-nium substrates are covered by a native titanium oxide layer. Together with the electrodeposited calcium phosphate layer a clear antibacterial effect has been observed. Electrodeposited calcium phosphate coatings were also dipped in aqueous copper sulphate solutions to convert partly calcium phosphate to copper phosphate. The antibacterial properties of such coatings can be controlled and adjusted to the clinical setting and to specific indications. Patient-tailored antibacterial treatments seem to be possible and may be of special interest for high-risk operations.

Abstract: Nano size silver films were deposited on the surface of regenerated cellulose films by magnetron sputtering, to impart antibacterial functionality to the cellulose films. Field emission scanning electron microscopy (FESEM) images revealed that the silver films were composed of nano size compact grains and the surface shape of the grains changed with changing sputtering power. As the power increased, the size of the nano silver grains increased and the number of grains decreased. Surface elemental analysis by energy dispersive spectrometry (EDS) showed a small amount of elemental silver on the surface. The antibacterial activity of the films was assessed by the shake flask test which measured the number of Staphylococcus aureus bacteria. The percentage reduction of the bacteria reached >99.9%.

Abstract: Polyaniline(PANI)/TiO2 nanocomposites are successful synthesized by one step-interfacial polymerization method. Morphologies and structures of the nanocomposites are characterized using SEM, FTIR, and XRD. The antibacterial properties of PANI/TiO2 nanocomposites on Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Bacillus megateriu and Bacillus cereus are tested. The effect of molar ratio of aniline and tetrabutyl titanate on structures and antibacterial properties are also been explored. The results show that the content of tetrabutyl titanate has a obvious influence on structure and morphologies of the nanocomposites. PANI/TiO2 nanocomposites have antibacterial properties especially on Staphylococcus aureus and Escherichia coli, which shows a best antibacterial property when the molar ratio of aniline to tetrabutyl titanate is 3:2.

Abstract: A composite, TiO2/AgY, was prepared by impregnation of tetrabutyl titanate solution on NaY zeolite, subsequent calcination at 500°C and ion-exchange with AgNO3 solution. XRD.SEM, TEM and EDAX were used to characterize the crystalline phase, the particle size of the formed nano-materials and the relative contents of atoms in TiO2/AgY and NaY zeolite, respectively. TiO2 nanoparticles with the size of 5-8 nm were found to form on the external surface of the zeolite. About half of Na+ in NaY zeolite is exchanged into Ag+. The as-prepared material exhibits excellent antibacterial activity and decompose E. coli using ultraviolet radiation as light resource.